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have an average dissolved solids content of about 2,450 ppm. For the purpose of determining Wellton-Mohawk effluent mineral concentrations it is assumed that the dissolved solids content of water produced by new wells in high saline ground-water areas would average about 13,000 ppm and the new wells in the less saline areas would produce water that would average about 3,700 ppm of dissolved solids. Table 15 shows the estimated average salinity content of the Wellton-Mohawk drainage channel discharge by months and the projected quality of water delivered to Morelos Dam after completion of Phase 1 construction. These salinity estimates are subject to such modification as may be necessary to maintain a satisfactory ground-water level in the Wellton-Mohawk Irrigation District. Such modifications can only be determined by the analog studies. It is emphasized that in order to meet the October completion date for Phase 1, funds must be available early in March of 1963. Even then, a "crash" construction program will be required, with highest priority necessarily given to this work by all offices concerned. 2. Phase 2. Construction of work included in Phase 2 is predicated on construction of facilities described under Phase 1 and must be considered an inseparable part of the recommended plan. Operation, after Phase 2 construction is completed, is based on selective pumpage in the Wellton-Mohawk area as in Phase 1 with the addition of increased evacuation channel capacity that will permit unbalanced pumping of wells, i. e., increased pumping during the months of higher water demand by Mexico and less pumping during the winter months. In addition, twelve more wells would be constructed 87Epson Perfection 4870 Photo, 400 dpi, 8 bit, 8,819,712 byte